Reinforcement for a tooth filling



Jan. 16, 1951 F. TOFFLEMIRE 2,538,486

REINFORCEMENT FOR A TOOTH FILLING 2 Sheets-Sheet 1 Filed Jan. 12, 1948.41, I I l I I l I l INVENTOR.

' B:E.IB\I};JA;MU\I E TOFFLEMIRE ATTORNEYS 1 1951 B. F. TOFFLEMIRE V2,538,486

REINFORCEMENT FOR A TOOTH FILLING Filed Jan. 12, 1948 2 Sheets-Sheet 2INVENTOR. BENJAMIN FTOFFLEMIRE mizw aw ATTORNEYS matrix bands.

Fatented Jan. 16, 1951 a UNITED STATES PATENT O FFICE 2,538,486 I i VREINFORCEMENT FoRin- 'roo'rn- FILLING Benjamin F.. maem Lafayette;Calif. Application January 12, 1948'; Serial bio. 1,721

6 Claims.

, The present invention relates to improvements nearly meets therequirements of the majority of patients than any other filling materialthat hast been used in modern dentistry. Amalgam isu'sed' successfullyby practically every dentist ingeneral practice. 7

Z; some of the most serious'objections to the use of amalgam in the pasthave been its lack of marginal edge-strength; its limited ability toresisti f'flow" when subjected to heavy masticatory stresses; itsdimensionalinstability, particularly when the amalgam restoration isexposed to appreciable variations and elevations of mouth temperatureswhile eating, thereby accentuating the .spheroidal tendency'of theeutectic mixture, or low fusing alloy; and, finally, its inability to.maintain permanently well-rounded contacts.

' ln order to overcome all of these inherent weaknesses at one fellswoop, I have devised a -reinforcement for the amalgam fillings. Forthis "purpose, I provide specially'formed, instantly These inserts have.

adaptable, silver inserts. hardened contact points capable ofwithstanding permanent rugged service without either loss of theoriginal summits of convexity of the contact points, or loss of theoriginal normal interproxi- For restoring decayed and broken down teeth,

Jim

where the band contacts an adjoining tooth or teeth. 'IlTOn form; thematrix'band is nickel platedin sections soas to withstand chemicalactionzbythe amalgam. Unplated sections-are provided on the matrix bandin the region of the notch or notches. These unplated sections aredisintegrated bytheamalgam, thus allowing the remaining portionsof theband to be removed mal embrasures and injury to the interseptal gingivaltissues-all too often noticed in using amalgam which has not beenstabilized by block silver reinforcing,

As an additional refinement in the use of reinforced amalgam work, Iprovide specially-formed 7 These bands may be applied readily to a toothby the dental matrix retainer disclosed in my copending application,Serial No. 721,995, filed in the United States Patent Ofilce on January14, 1947, now Patent. No. 2,502,903, so

-missal of the patient-an achievement hereto fore found impossible.

My matrix band adapts itself to the irregular conformation of V thetooth upon which it is placed, and is notched at the point, or points,

faces-only;

easily-1 1 In a modified form my matrix band is entirely nickelplated.The-notch, or notches, which receive the end, or ends, of the insertsduring the packing and condensing of the amalgam, facilie' ta-tebreaking the band into sections prior tore- 'm'oval-from thetooth. Otherobjects-and advantages will appear as thespecification continues, andthe novel features will-be set forth in the claims hereunto-appended.-For abetter understanding of my invention, reference should behad to theaccompanyingdrawings; forming part of this application m which: Y YFigure l-is ail-isometric view of a lower right first-molar having amesial-occlusal-distal cavity prepared therein, and further shows amatrix band clamped around'the axial contour of the teeth by one: of mydental matrix retainers;

Figure 2 is-a longitudinal sectional view taken through the samemolarfromthe mesial to. the

distal surfacesgand disclosing the cavity partially packedwithamalgamand the: insert anchored to the amalgam; Figure 3 is a top plan. view ofthe-completely: filled tooth asseenfrom the occlusalipl'ane;

Figure 4. is a longitudinal sectional view takenalong the line. IV'--I Vof Figure 3; Figure'S is an elevation of a post-provided on thereinforcing. insert at either the distal or mesialend of the insert.Figure 6 is a face viewof. one form of my matrix band; I 5 Figure 7 is aface view of a modified. form of matrix band;-

Figure 8 is a view similar to Figure 4, but showing the cavity preparedin the distal-occlusal sure Figure 9 is a top plan vievrof Figure '8,looking from-the occlusal plane; and .1 Figure 10 isa view -milar toFigure 9, but add ing a ling-ual-occlusalIrelnforcing insert.

While I have shown only the preferred forms of my invention, it shouldbe understood that various changes'o'r modifications, may be'made withinthe scope of the annexed claims without departing from th'- spiritthereof.

Referring to the drawings in detail, Figures 1 to 4', inclusive,illustrate a lower right first molar, which isfindicated generally at A.This tooth is situated between the second bicuspid B and the secondmolar 'C'.

In order that the terms hereinafter used may be fully understood,various parts of the lower right first molar A are designated byreference numeral as follows: |--buccal surface (toward cheek) 2-lingualsurface (tongue side); 3- mesial surface (toward mesial plane of thebody) 4-distal surface (remote or away from the mesial plane) 5occlusalsurface; and (gum) border. This molar has a mesial-occlusaldistal cavityD therein, the various parts of which are .designated by referencenumerals as follows:' 'l-fioor of cavity; 8axial walls; 9--gingivalfioors; and icavo surfaces. The axial contour of the tooth is indicatedat H, and this contour is conical-shapedand tapers inwardly toward theroots or fangs l2. a

Figure 1 shows a matrix band E, which encircles the molar A and is drawntightly against the axial contour l l of the tooth by a dental matrixretainer F. This retainer is disclosed and described in detail in mycopending application, Serial No. 721,995, filed January 14-, 1947, andreferred to in the objects of this application.

Briefly described, the retainer F includes a barlike frame l4 on which amatrix-clampingblock I is slidably mounted. The frame M has a head Itthereon, which defines four parallel and spaced-apart fingers ll, [8, l9and 20. The ends H of the matrix band E are accommodated in adiagonally-extending slot 22 formed in the block l5, and are clampedthereto by a spindle 23 that isthreaded into the block. The spindle isrotated by an operating knob 24. A rotatable internallythreaded sleeve25 is held against endwise move- 6-gingival ment relative to the framel4. When this. sleeve is turned, the spindle 23 and the clamping blockl5 are advanced or retracted relative to the head I6.- -In Figure l, Ishow the matrix band as passing between the fingers I'I-I8 and thenguided through the slot providedbetween the fingers l8--20. When theblock [5. is retracted, the matrix band E. will be drawn up tightlyagainst the axial contour ll of the tooth A.

The matrix band E illustrated in Figure 6 is made of a material, such asbrass, that will be. acted upon chemically byamalgam and cause thematerial to disintegrate. The band has nickel plated" sections 26, whichwill resist chemical reactionof. the amalgam. The intermediate sections2'! of the band are unplated and areexposed to the action of the amalgamduring packing of It will be noted from Figure 6 that thematrix themember toward the cavo surfaces ll).

posed at the bottom thereof. Figures 3 and 4 disclose the tops 32 of theposts as being wider than the member 29 so as to project laterallybeyond The bar-like member 29 and the posts 30 preferably are made ofsilver so that amalgam will bond chemically thereto.

Lugs 33 of hardened material, such as gold,

project from opposing faces of the posts 30 in 7 directions to contactwith the teeth B and C, which are disposed on opposite sides of themolar A in which an amalgam filling will be packed. These lugs projectinto the notches 28 of the matrix band E and are supported by the latter(see Figure 2).

An important structural feature of the insert G is the zig-zagconfiguration of the bar-like member 29. The over-all length of theinsert will be made so as to correspond approximately with the distancebetween the teeth BandC. However, in the event that the lugs 33 do notcontact with the teeth B and C, the length of the member 29 can beextended by merely gripping opposite corners 34 of the member with apair of pliers, orthe like, and squeezing the jaws of the pliers towardone another to elongate the member 29. In case the member 29 isover-extended, the tips of the lugs 33 can be ground down. The primarypoint to bear in mind is that the lugs 33 must contact with the teeththat are located on opposite sides of the tooth in which the insert isapplied.

Prior to introducing the insert E into the cav- V ity D, a body ofamalgam H,- or partial filling, is applied over the cavity floor 1, theaxial walls 8 and gingival floors 9. The body H of amalgam extends tothe inner walls of the matrix band.

band E is curved lengthwise when the band is fiat.

The intermediate portion of the band will become conical-shaped whendrawn tightly around a tooth (see Figure 2). The band extends downwardlyat least togthe 'gingival fioor 9.

v Referring now to Figures 2 to 5, inclusive, I show an insert G, whichis made for reinforcing a mesial-occlusal-distal filling. This insertincludes a bar-like member 29 of zig zag configuration, as shown inFigure 3, and designed for overlying the main cavity floor 'l' in spacedrelation therewith. The ends of this member have posts 30 dependingtherefrom. Each post tapers to a point 3.! dis-v floor I and theposts'substantially parallel relative to the axial walls 8. The lugs 33will come to rest in the notches 28 and contact the teeth B and C.Figure 2 shows the restoration up to this point, and the matrix band Bis still in place around the axial contour of the. tooth A. The body ofamalgam H Will unite. chemically with theinsert.

.As the next step, an upper'layerof amalgam Jis packed and condensedover the insertfas shown in Figures 3 and 4. By this time, the unplatedsections 21 of the matrix band have dis: integrated, or at leastweakened, by the amalgam acting on the brass. The dental matrix retainerF is removed and the plated sections 26 of the band E are removed. Themember 29 could be arranged in registry with the occlusal surfac of theamalgam filling, 'if desired. The posts 30'project laterally toward thecavo surfaces In so as to reinforce the amalgam filling disposed betweenthe surfaces It atv the mesial and distal portions of the tooth.Normally, this is a very vulnerable part of the filling. I

Figure illustrates amodified form of a ma? trix band, which isdesignated at E. In this modification, the entire surface of the band isnickel plated, as suggested by the color shading. This band has the sameshape as the one shown in Figure 6, and is provided with notches 28 inits upper edge. After the amalgam filling has been packed and condensed,the band E is broken at points below the notches 28, as indicated by thebreak lines 35 in Figure 7. This will allow the band E to be withdrawnin three sections.

, Turning now to Figures8 and 9, it will be noted that a distal-occlusalcavit D' has been prepared in a tooth A. The insert G is really one-halfof the insert G previously described. Accordingly, like referencenumerals will beapplied to corresponding parts. In this form, the end29a abuts the central axial wall 35 of the cavity, while the lug 33 hascontact with the tooth C. Figures 8 and 9 disclose the tooth A ascontacting with an adjacent tooth B. The method of filling the cavity Din Figures 8 and 9 is identical with that described in connection withFigures 1 to 5, inclusive. Also, the insert is made of silver so that itwill unite chemically with the amalgam bodies H and J. I

Figure 10 is identical with Figure 9, excepting that a lingual-occlusalcavity D" has been added in the tooth A". A silver insert G has beenplaced in this cavit to reinforce the amalgam filling K therein. Theteeth on opposite sides of the tooth A" are designated at B" and C". Thetooth A has a distal-occlusal cavity D therein in which an insert G isdisposed to reinforce the amalgam filling J". The method of restoringthe tooth A" is the same as that set forth in connection with Figures 8and 9, except for the addition of the insert G".

It is obvious that the cavities in Figures 8 to 10, inclusive, couldextend in a mesial-occlusal direction, if the decay in the tooth beingfilled required such a cavity to be prepared.

The inserts that I have disclosed may be applied readily and areprovided with hardened lugs, or contact points, that will withstandrugged service without loss of the original summits of convexity of thecontact points, or loss of the original normal interproximal embrasures.will prevent injury to the interseptal gingival tissues. The amalgamfillings will withstand heavy masticatory stresses, maintain their dimensions and resist spheroidal tendency. Also, they will maintainwell-rounded contacts. No galvanic action will take place, and theinserts become permanentl bonded to theamalgam fillings. The hardenedlugs on the inserts prevent food from packing between adjacent teeth.The strength of the fillings will be increased tremendously overordinary amalgam fillings.

Although I have referred to using my inserts for reinforcing amalgamfillings, I wish to make it clear that other types of fillings, such asporcelain, could be reinforced with the inserts. When amalgam isemployed, it is desirable to form the inserts from silver, since theamalgam and silver inserts will bond together chemically. The lug orlugs 33 may be made from any suitable hardened metal, for instance, lowcarat gold solder or other case-hardened metal, and I do not wish to belimitedto gold alone.

I claim:

1. As an article of manufacture: a bar-like member designed to beembedded in a filling of a tooth to reinforce the filling; a postdepending from one end of the member for embedment in the filling; and arestricted lug projecting from the post on the side of the latteropposite to the member; the lug being dimensioned to extend beyond theaxial contour of the tooth to provide a restricted interproximal contactpoint bearable against an adjacent tooth.

2. As an article of manufacture: a bar-like member designed to beembedded in a filling of a They tooth to reinforce the filling; a postdepending from one end .of the member for embedment in the filling; anda restricted lug projecting from the post on the side of the latteropposite to the member; the lug being dimensioned to extend beyond theaxial contour of the tooth to provide a restricted interproximal contactpoint bearable against an adjacent tooth; the bar-like member beingzig-zag in configuration, and defining con-' volutions winding back andforth on first one side of the member and then on the other; the memberbeing sufiiciently pliable for flattening out of its convolutions toextend the over-all length of the member.

3. As an article of manufacture: a bar-like member designed to beembedded in a filling of a tooth to reinforce the filling; a pair ofposts dependingfrom opposite ends of the member for embedment in thefilling; and preformed lugs projecting from the posts on the sidesthereof opposite to the member; the lugs being dimensioned to extendbeyond the axial contour of the tooth to provide restrictedinterproximal contact points bearable against teeth disposed on themesial and distal aspects of the tooth in which the member is disposed.

4. As an article of manufacture: a bar-like member designed to beembedded in a filling of a tooth to reinforce the filling; a pair ofposts depending from opposite ends of the member for embedment in thefilling; and preformed lugs projecting from the posts on the sidesthereof opposite to the member; the lugs being dimensioned to extendbeyond the axial contour of the tooth to provide restrictedinterproximal contact points bearable against teeth disposed on themesial and distal aspects of the tooth in which the member is disposed;the bar-like member being zig-zag in configuration, and definingconvolutions Winding back and forth on first one side of the member andthen the other; the memher being sufiiciently pliable for flattening outof its convolutions to spread the posts farther apart.

5. In combination: a looped matrix band having a notch fashioned in anupper edge thereof; and a bar-like member disposed within the loop ofthe matrix band; the member having a lug projecting into the notch ofthe matrix band and supporting one end of the member.

6. In combination: a looped matrix band having notches fashioned in anupper edge of the band at diametrically-opposed sections of the loopedband; and a bar-like member disposed within the loop of the matrix band;the member having lugs projecting into the notches of the matrix bandand supporting both ends of the member.

BENJAMIN F. TOFFLEMIRE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Bull May 5, 19,86

